Hostname: page-component-cd9895bd7-jkksz Total loading time: 0 Render date: 2024-12-27T07:20:43.690Z Has data issue: false hasContentIssue false
  • English
  • Français

Transport and Exchange Behavior of Ions in Bentonite During Electro-Osmotic Consolidation

Published online by Cambridge University Press:  01 January 2024

Hui Wu ,
Liming Hu ,
Lin Zhang  and
Qingbo Wen
Hui Wu
Affiliation:
State Key Laboratory of Hydro-Science and Engineering, Department of Hydraulic Engineering, Tsinghua University, Beijing 100084, P. R. China
Liming Hu*
Affiliation:
State Key Laboratory of Hydro-Science and Engineering, Department of Hydraulic Engineering, Tsinghua University, Beijing 100084, P. R. China
Lin Zhang
Affiliation:
State Key Laboratory of Hydro-Science and Engineering, Department of Hydraulic Engineering, Tsinghua University, Beijing 100084, P. R. China
Qingbo Wen
Affiliation:
State Key Laboratory of Hydro-Science and Engineering, Department of Hydraulic Engineering, Tsinghua University, Beijing 100084, P. R. China
*
*E-mail address of corresponding author: gehu@tsinghua.edu.cn
Rights & Permissions [Opens in a new window]

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

Electro-osmotic consolidation is considered to be an efficient technique for dewatering and consolidation of soft soil. In the present study, four experiments were conducted on a Na-rich bentonite using two reactive electrodes (copper and iron) and two inert electrodes (graphite and stainless steel) to study the transport and exchange behavior of ions during electro-osmotic consolidation. The results showed that the changes in pH and ion contents were limited to the zone close to the electrode due to the buffering capacity of bentonite and the significant reduction in electric current density. The ion concentration profiles indicated that Na+ ions were largely responsible for carrying the pore water to the cathode. The reactive electrodes are better at transporting Na+ ions and therefore induce better drainage than inert electrodes. Ion-exchange reactions occurred between the Cu2+ and Fe2+/Fe3+ ions released and pre-existing Na+ ions in the electrical double layer, causing decreased water adsorption capacity and plasticity index. The swelling and shrinkage characteristics of the bentonite were thus reduced, and electroosmotic consolidation may therefore provide a new way to improve the stability of expansive soils and slopes.

Keywords

Electro-osmotic ConsolidationElectrode MaterialGeotechnical PropertyIon ContentIon ExchangeNa-rich Bentonite
Type
Article
Information
Clays and Clay Minerals , Volume 63 , Issue 5 , October 2015 , pp. 395 - 403
Copyright
Copyright © The Clay Minerals Society 2015

References

Abu Rabi-Stankovic, A. Milutinovic-Nikolic, A. Jovic-Jovicic, N. Bankovic, P. Zunic, M. Mojovic, Z. and Jovanovic, D., 2012 p-nitrophenol electro-oxidation on a BTMA+-bentonite-modified electrode Clays and Clay Minerals 60 291–299.CrossRefGoogle Scholar
Acar, Y.B. and Alshawabkeh, A.N., 1993 Principles of electrokinetic remediation Environmental Science & Technology 27 2638–2647.CrossRefGoogle Scholar
Acar, Y.B. Gale, R.J. Putnam, G.A. Hamed, J. and Wong, R.L., 1990 Electrochemical processing of soils: theory of pH gradient development by diffusion, migration, and linear convection Journal of Environmental Science and Health A25 687–714.Google Scholar
Al-Hamdam, A.Z. and Reddy, K.R., 2008 Transient behavior of heavy metals in soils during electro-kinetic remediation Chemosphere 71 860–871.CrossRefGoogle Scholar
Bjerrum, L. Moum, J. and Eide, O., 1967 Application of electroosmosis to a foundation problem in Norwegian quick clay Géotechnique 17 214–235.CrossRefGoogle Scholar
Burnotte, F. Lefebvre, G. and Grondin, G., 2004 A case record of electro-osmotic consolidation of soft clay with improved soil-electrode contact Canadian Geotechnical Journal 41 1038–1053.CrossRefGoogle Scholar
Cameselle, C. and Reddy, K.R., 2013 Effects of periodic electric potential and electrolyte recirculation on electrochemical remediation of contaminant mixtures in clayey soils Water, Air, & Soil Pollution 224 1–13.CrossRefGoogle Scholar
Casagrande, L., 1948 Electroosmosis in soils Géotechnique 1 159–177.CrossRefGoogle Scholar
Casagrande, L., 1983 Stabilization of soils by means of electroosmotic state-of-art Journal of Boston Society of Civil Engineers ASCE 69 255–302.Google Scholar
Chang, H.W. Krishna, P.G. Chien, S.C. Ou, C.Y. and Wang, M.K., 2010 Electro-osmotic chemical treatments: effects of Ca2+ concentration on the mechanical strength and pH of kaolin Clays and Clay Minerals 58 154–163.CrossRefGoogle Scholar
Chien, S.C. Ou, C.Y. and Lee, Y.C., 2009 A novel electroosmotic chemical treatment technique for soil improvement Applied Clay Science 50 481–492.CrossRefGoogle Scholar
Chien, S.C. Ou, C.Y. and Lo, W.W., 2012 Electro-osmotic chemical treatment of clay with interbedded sand Geotechnical Engineering 167 62–71.Google Scholar
Esrig, M.I., 1968 Pore pressures, consolidation and electrokinetics Journal of the Soil Mechanics and Foundation Engineering Division ASCE 94 899–921.CrossRefGoogle Scholar
Glendinning, S. Jones, C.J.F.P. and Pugh, R.C., 2005 Reinforced soil using cohesive fill and electrokinetic geosynthetics International Journal of Geomechanics ASCE 5 138–146.CrossRefGoogle Scholar
Heuser, M. Weber, E. Stanjek, H. Chen, H. Jordan, G. Schmahl, W.W. and Natzeck, C., 2014 The interaction between bentonite and water vapor. I: Examination of physical and chemical properties Clays and Clay Minerals 62 188–202.CrossRefGoogle Scholar
Hu, L.M. and Wu, H., 2014 Mathematical model of electroosmotic consolidation for soft ground improvement Géotechnique 64 155–164.CrossRefGoogle Scholar
Hu, L.M. Wu, W.L. and Wu, H., 2012 Numerical model of electro-osmotic consolidation in clay Géotechnique 62 537–541.CrossRefGoogle Scholar
Katz, A. Xu, M. Steiner, J.C. Trusiak, A. Alimova, A. Gottlieb, L. and Block, K., 2013 Influence of cations on aggregation rates in Mg-montmorillonite Clays and Clay Minerals 61 1–10.CrossRefGoogle Scholar
Lamont-Black, J. and Weltman, A. (2010) Electrokinetic strengthening and repair of slopes. Ground Engineering, April, 28–31.Google Scholar
Lefebvre, G. and Burnotte, F., 2002 Improvement of electroosmotic consolidation of soft clay by minimizing power loss at electrodes Canadian Geotechnical Journal 39 399–408.CrossRefGoogle Scholar
Lo, K.Y. and Ho, K.S., 1991 The effects of electroosmotic field treatment on the soil properties of a soft sensitive clay Canadian Geotechnical Journal 28 763–770.CrossRefGoogle Scholar
Lorenz, P.B., 1969 Surface conductance and electrokinetic properties of kaolinite beds Clays and Clay Minerals 17 223–231.CrossRefGoogle Scholar
Micic, S. Shang, J.Q. Lo, K.Y. Lee, Y.N. and Lee, S.W., 2001 Electrokinetic strengthening of a marine sediment using intermittent electric current Canadian Geotechnical Journal 38 287–302.CrossRefGoogle Scholar
Mitchell, J.K. and Soga, K., 2005 Fundamentals of Soil Behavior 3rd edition USA John Wiley & Sons, Inc.Google Scholar
Otsuki, N. Yodsudjai, W. and Nishida, T., 2007 Feasibility study on soil improvement using electrochemical technique Construction and Building Materials 21 1046–1051.CrossRefGoogle Scholar
Ou, C.Y. Chien, S.C. and Wang, Y.G., 2009 On the enhancement of electroosmotic soil improvement by the injection of saline solutions Applied Clay Science 44 130–136.CrossRefGoogle Scholar
Reddy, K.R. and Saichek, R.E., 2002 Effect of soil type on electrokinetic removal of phenanthrene using surfactants and cosolvents Journal of Environmental Engineering 129 336–346.CrossRefGoogle Scholar
Ricart, M.T. Pazos, M. Cameselle, C. and Sanroman, M.A., 2008 Removal of organic pollutants and heavy metals in soils by electrokinetic remediation Journal of Environmental Science and Health Part A 43 871–875.CrossRefGoogle ScholarPubMed
Shang, J.Q. Lo, K.Y. and Quigley, R.M., 1993 Quantitative determination of potential distribution in Stern-Gouy double layer model Canadian Geotechnical Journal 31 624–636.CrossRefGoogle Scholar
Stawinski, J. Wierzchos, J. and García González, M.T., 1990 Influence of calcium and sodium concentration on the microstructure of bentonite and kaolin Clays and Clay Minerals 38 617–622.CrossRefGoogle Scholar
Svensson, P.D. and Hansen, S., 2013 Redox chemistry in two iron—bentonite field experiments at Äspöhard rock laboratory, Sweden: An XRD and Fe K-edge XANES study Clays and Clay Minerals 61 566–579.CrossRefGoogle Scholar
Tong, M. Yuan, S.H. Zhang, P. Liao, P. Alshawabkeh, A.N. Xie, X.J. and Wang, Y.X., 2014 Electrochemically induced oxidative precipitation of Fe (II) for As (III) oxidation and removal in synthetic groundwater Environmental Science & Technology 38 5145–5153.CrossRefGoogle Scholar
Van Olphen, H., 1977 An Introduction to Clay Colloid Chemistry New York Interscience.Google Scholar
Vane, L.M. and Zang, G.M., 1997 Effect of aqueous phase properties on clay particle zeta potential and electro-osmotic permeability: Implications for electro-kinetic soil remediation processes Journal of Hazardous Materials 55 1–22.CrossRefGoogle Scholar
Wu, H. and Hu, L.M., 2013 Analytical solution for axisymmetric electro-osmotic consolidation Géotechnique 63 1074–1079.CrossRefGoogle Scholar
Wu, H. and Hu, L.M., 2014 Microfabric change of electroosmotic stabilized bentonite Applied Clay Science 101 503–509.CrossRefGoogle Scholar
Wu, H. Hu, L.M. and Wen, Q.B., 2015 Electro-osmotic enhancement of bentonite with reactive and inert electrodes Applied Clay Science 111 76–82.CrossRefGoogle Scholar
Zhang, G.P. Germaine, J.T. and Whittle, A.J., 2003 Effects of Fe-oxides cementation on the deformation characteristics of a highly weathered old alluvium in San Juan, Puerto Rico Soils and Foundations 43 119–130.Google Scholar
Zhang, G.P. Germaine, J.T. Whittle, A.J. and Ladd, C.C., 2004 Index properties of a highly weathered old alluvium Géotechnique 54 441–451.CrossRefGoogle Scholar
Zhang, P. Jin, C.J. Zhao, Z.H. and Tian, G.B., 2010 2D crossed electric field for electrokinetic remediation of chromium contaminated soil Journal of Hazardous Materials 177 1126–1133.CrossRefGoogle ScholarPubMed
Zhou, Y.D. Deng, A. and Wang, C., 2013 Finite-difference model for one-dimensional electro-osmotic consolidation Computers and Geotechnics 54 152–165.CrossRefGoogle Scholar
Zhuang, Y.F. and Wang, Z., 2007 Interface electric resistance of electroosmotic consolidation Journal of Geotechnical and Geoenvironmental Engineering 133 1617–1621.CrossRefGoogle Scholar